This invention relates to a mounting apparatus for a motor, and particularly to a mounting apparatus for a motorized lock actuator that electrically locks and unlocks a cylindrical lockset mounted in a door. More particularly, this invention relates to a mounting apparatus for an electromechanical lock actuator mechanism in a door-mounted cylindrical lockset having an outside door handle that can be locked against rotation.
Cylindrical locksets are well known and such a lockset is operated to lock and unlock a door by rotating inside and outside door knobs or lever handles connected to the lockset. Typically, a cylindrical lockset is used to connect a door handle to a retractable latch bolt. Each cylindrical lockset can include various mechanical linkages and locking mechanisms of the types described in the following paragraphs.
In use, a user can often rotate either the inside or outside door handle to operate the mechanical linkage mounted inside the lockset. This enables the user to retract a spring-biased latch bolt connected to the cylindrical lockset from a projected position extending outside the door and engaging a side slot formed in a doorjamb to a retracted position inside the door. The user is now free to swing the door on its hinges from a closed position to an opened position.
A locking mechanism of some kind is usually mounted in the cylindrical lockset. Such a locking mechanism is often actuated using a key or a button to lock or unlock the outside door handle. Typically, the locking mechanism is configured so that it can be actuated either by turning a key inserted into a keyway formed in the outside door handle or by turning or pushing a button mounted in the inside door handle. For example, cylindrical locksets using mechanical locking mechanisms are disclosed in U.S. Pat. Nos. 3,955,387 to Walter E. Best et al. and 4,437,695 to William R. Foshee. Each of these locksets include a spring-loaded mechanical locking bar and turn button. The turn button is mounted in the inside doorknob and is operable to allow a user to actuate the mechanical locking bar and thereby control locking and unlocking of the outside doorknob.
It is also known to use a miniature motor and locking linkage mounted inside a cylindrical lockset to control locking and unlocking of the outside doorknob or handle. See, for example, U.S. Pat. Nos. 5,083,122 to Keith S. Clark, 5,018,375 to Clay E. Tully, and 5,421,178 to Lyn E. Hamel et al. The '178 patent is assigned to the same assignee as the present invention and is incorporated herein by reference, for descriptions of electromechanical locking mechanisms.
It has been observed that motor-mounts designed to accept electrical motors for use in locking mechanisms are typically coupled within the lockset using additional fasteners. The use of multiple fasteners has been necessary to ensure that the motor-mount does not move or rotate within the lockset upon rotation of the inside door handle. However, it has been discovered that additional fasteners can make a lockset having a motor-actuated locking mechanism awkward to assemble and disassemble. A motor-mount made to hold an electrical motor in a fixed position within a lockset without using multiple fasteners would simplify assembly/disassembly of the motor-actuated locking mechanism, minimize necessary inventory for manufacture assembly and of the locking mechanism, and thus reduce the overall cost of the locking mechanism to the consumer.
It has been further observed that electrical locksets with a motor having a wire harness extending outwardly therefrom are often subject to accidental harness pull-out. In addition, the wire harness itself can often interfere with the surrounding moving or rotating lockset components. A motor-mount that provides a protected space for the wire harness and that minimizes accidental pull-out would be a welcome improvement over conventional mount apparatus.
According to the present invention, a motor-mount apparatus is provided for use in holding a motor housing within a motor-actuated cylindrical lockset. The motor-mount apparatus includes a substantially flat plate formed to include an aperture for receiving a motor-controlled lock actuator therethrough and locking tabs extending into the aperture to hold the motor housing in a fixed position within the lockset. Thus, the motor-mount apparatus is prevented from either rotating or sliding axially within a rotatable handle sleeve of the lockset.
In preferred embodiments of the present invention, the motor-mount apparatus includes a motor housing with an inner end, an opposite outer end having locking means thereon to engage the locking tab of the flat plate, and a cylindrical side wall extending between the opposite inner and outer ends. In addition, the motor housing preferably incorporates a bottom wall at its inner end that interlocks the motor thereto and prevents unwanted rotational movement of the motor within the cylindrical side wall of the housing. In addition, the cylindrical side wall of the motor housing includes an inner surface that defines a cavity sized for insertion of the motor therein and a locking flange that extends into the cavity to fasten the motor within the cylindrical side wall.
The inner surface of the cylindrical side wall is formed to include an internal wire channel therein. The wire channel extends between the opposite ends of the housing to accommodate the routing of a wire harness extending from the motor away from the motor-mount assembly. The routing of the wire harness through the protected space of the wire channel aids in eliminating eccentric alignment of the motor.
The wire harness of the motor is protected from wear by a wire-protection cap. This cap incorporates snap-in type legs which interlock into appropriate leg-receiving windows formed in the flat plate. Thus, the wire harness may be routed from the outer end of the housing, through the aperture of the flat plate, and up through the protective cap. The wire-protection cap itself includes a molded-in wire channel for routing the harness away from the motor-mount apparatus and outside of the lockset. In addition, a wire hold-down feature is preferably incorporated within the wire channel, thus providing a slight interference fit with the wire harness, thus reducing a potential accidental pull-out condition.
In an alternative embodiment of the present invention a motor housing is provided for use in conjunction with a lockset having a stationary hub with a slot therein and a rotatable handle sleeve positioned within the hub and formed to include a passageway therethrough. The alternative motor housing includes an outer end having a flexible locking tab thereon. This locking tab will interlock with the conventional hub slot to provide both rotational and axial resistance to movement of the motor-mount apparatus. It is understood that locksets often include flat side plates which abut the stationary hub. Thus, it is contemplated that the locking tab will also stop against a back surface of the flat side plate to prevent axial movement of the motor housing.
In a preferred embodiment, the locking tab incorporates a slotted feature therein. Thus, a wire harness extending outwardly from motor may be routed through the locking tab and away from the motor-mount apparatus. Preferably the locking tab is flexible so that it may deflect inwardly into cavity during assembly and then snap or deflect upward into the hub slot in the assembled position. This flexibility aids in assembly of the motor-mount apparatus into the existing lockset.
The motor-mount apparatus of the present invention supports a motor therein and is easily mounted in certain conventional cylindrical locksets to permit a lockset to be converted from a fully mechanical lock actuator to a motorized lock actuator in the field or in the shop. In addition, development of the motor-mount apparatus was undertaken to reduce cost of locksets to the customer; simplify design for better ease of assembly/disassembly; reduce overall components to minimize inventory; prevent potential rotational friction between the motor-mount and a handle sleeve; provide better bearing surface between applicable components over a conventional lockset; supply additional wire protection; provide additional assembly flexibility; and incorporate a wire hold-down feature to help minimize potential wire pull-out.
Importantly, the motor-mount apparatus in accordance with the present invention creates a multifunctional part which reduces inventory and overall part/assembly costs. The motor-mount apparatus is much easier and quicker to assembly than conventional motor-mount assemblies, lending more flexibility to both the assembly line and the external customer. Because the motor-mount apparatus does not use small screws, assembly efforts are simplified and there is no fear of these screws loosening over time. In addition, the motor-mount apparatus is "field friendly" in regards to disassembly/reassembly if so needed such as repair and or retrofit situations.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.